1. Field of the Invention
The present invention relates generally to a copying machine, and more particularley to a copying machine equipped with an image editor adapted to edit an image on the basis of line marks marked on a document.
2. Description of the Prior Art
A copying machine is known which is capable of reading a mark or marks on a document and editing on the basis of the marks read out from the document as desired: for example, a masking is effected by erasing an image in the area indicated by the mark or the trimming is effected by erasing images in other areas than the area indicated by the mark. An example of such a marker editing function is shown in FIG. 4(a), wherein a first line mark 72 extending in the scanning direction of an optical system and a second line mark 73 extending orthogonal to the scanning direction are marked on a document 71 and the area indicated by the coordinates of these first and second line marks 72 and 73 is determined as an editing area 74.
However, with this known art copying machine, in the editing mode in which the editing area is determined by the coordinates in the scanning direction of the optical system and the coordinates orthogonal to that direction, as described above, if the longitudinal and crosswise dimensions of each of the line marks 72 and 73 are respectively greater than a given dimension, both dimensions are recognized as constituting separate coordinates. This means that when, as shown in FIG. 4(b), a first line mark 75 and a second line mark 76 are both marked in thick lines on a document 71, the widths of the first and second line marks 75 and 76 are also recognized as constituting coordinates, resulting in the setting of an undesired editing area 77 in addition to the desired editing area 74. Therefore, the problem is that editing is also done on the editing area 77 and a desired image cannot be produced in the marker editing mode.
Another editing method is also known, which is disclosed in Japanese Laid-Open Patent Publication No. 57-56859. Under this method a portion of a document to be copied is previously marked in a distinct color against a portion to be not copied, and the color outlined portion is scanned by an extra sensor. In response to the signal, a latent image in an area other than the colored outlined portion is erased. This method must have multiple sensors arranged in a main scanning direction so as to detect a copying area.